The use of poly(arylene sulfide) resins for injection molding is well known in the art. Poly(arylene sulfide) resins suitable for injection molding generally have a melt flow rate of less than about 100 grams per 10 minutes. Such resins can be prepared by processes such as described No. in U.S. 3,919,177. Even though these processes yield resins that are suitable for injection molding, the rate of production is low and the cost high. Alternately, suitable resins can be made by air curing the resins produced by processes described in U.S. No. 3,354,129. Air curing can require up to 30 hours, and darkens the resin, both undesirable features. The high melt flow rate resins produced by the referenced processes are not economically altered to the desired melt flow rate. The inclusion of a branching agent such as 1,2,4-trichlorobenzene as a comonomer in the resin preparation process is a further alternative to producing the desired resins. The presence of branching agents can yield resins undesirably low in ductility and mechanical properties. The problems encountered in the alternative approaches to provide a satisfactory poly(arylene sulfide) resins remain.
Accordingly, it is an objective of the invention to provide a process for altering the melt flow rate of poly(arylene sulfide) resins. It is a further objective to provide a poly(arylene sulfide) composition for injection molding. A still further objective is to provide a poly(arylene sulfide) composition of reduced melt crystallization temperature.